Physical function in UK adults with osteogenesis imperfecta: a cross-sectional analysis of the RUDY study.
Orlando G., Pinedo-Villanueva R., Reeves ND., Javaid MK., Ireland A.
We describe the physical function in adults with osteogenesis imperfecta (OI) and explored clinical and non-clinical factors related to its impairment. Our data showed that physical dysfunction is a common feature of adults with OI, varying by OI severity, and mediated by the presence and quality of pain and fatigue symptoms. INTRODUCTION: There is a paucity of data describing physical function in adults with osteogenesis imperfecta (OI). We investigated the effects of OI and its severity on physical function and explored the relationship between physical function and number of fractures and symptomatology. METHODS: Adults with OI of different types were recruited from the RUDY study, an ongoing UK-based prospective cohort study. Participants completed demographic and clinical questions and questionnaires. These assessed physical function (SF-36), mobility (EQ-5D-5L and NEADL), fatigue (FACIT-F), and pain (SF-MQ-2). Scores were compared using parametric or non-parametric statistical analyses, whereas correlations between outcomes were examined using univariate and multivariate regression analysis. RESULTS: Seventy-eight adults with OI aged 43.5 ± 14.5 years were enrolled (type I, 32; type III, 11; type IV, 10; unknown type, 26). Physical function (PCS, SF-36) was significantly lower in all participants than normative values (p < 0.001) and in type III than type I (p = 0.008). Mobility was significantly different across the types (EQ-5D-EL, p = 0.007; NEADL, p < 0.001), with type III having more severe problems, followed by types IV, unknown, and I. Physical function was associated with OI type (r = 0.26; p = 0.021), presence and quality of pain (r = - 0.57; p < 0.0001), and fatigue (r = - 0.51; p < 0.0001). Multivariate analysis revealed that physical function correlated independently with age, OI type, fatigue, and non-neuropathic pain. CONCLUSIONS: Individuals with OI display a marked deterioration in physical function during adulthood. This impairment varies in severity according to the OI phenotype and is associated with the presence of non-neuropathic pain and fatigue.